Holding device

Abstract

A technology is provided for improving the temperature uniformity of the mounting surface in a holding device. [Solution] The holding device comprises a plate-shaped portion having a mounting surface on which an object is placed, and a heater portion arranged inside the plate-shaped portion so as to face the mounting surface, the heater portion having a first region, a second region and a third region arranged to form at least a part of a ring shape when viewed in a plane on the mounting surface of the plate-shaped portion, and the first heater arranged in the first region, the second heater arranged in the second region and the third heater arranged in the third region are connected in parallel to each other.

Description

[Technical Field]

[0001] The present invention relates to a retaining device. [Background technology]

[0002] BACKGROUND ART Conventionally, a holding device provided with a heater for heating an object placed on a placement surface is known (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-317940 Summary of the Invention [Problem to be solved by the invention]

[0004] However, even with the prior art such as that of Patent Document 1, there is still room for improvement in the technology for improving the temperature uniformity of the mounting surface in the holding device.

[0005] An object of the present invention is to provide a technique for improving the temperature uniformity of the mounting surface in a holding device. [Means for solving the problem]

[0006] The present invention has been made to solve at least part of the above-mentioned problems, and can be realized in the following aspects.

[0007] (1) According to one aspect of the present invention, there is provided a holding device comprising: a plate-shaped portion having a mounting surface on which an object is placed; and a heater portion disposed within the plate-shaped portion so as to face the mounting surface, the heater portion having a first region, a second region, and a third region arranged to form at least a part of a ring shape in a plan view of the mounting surface of the plate-shaped portion, and the first heater disposed in the first region, the second heater disposed in the second region, and the third heater disposed in the third region are connected in parallel to each other.

[0008] According to this configuration, the plate-shaped portion has a mounting surface on which an object is placed, and includes a heater portion arranged to face the mounting surface. The heater portion has a first region, a second region, and a third region that are arranged to form at least a part of a ring shape when viewed from above on the mounting surface of the plate-shaped portion. A first heater, a second heater, and a third heater that are connected in parallel to each other are arranged in the first region, the second region, and the third region, respectively. As a result, the first heater, the second heater, and the third heater are each subjected to the same voltage, and the heat generation amount of each heater is inversely proportional to the magnitude of the electrical resistance of each heater. Therefore, even if there is variation in the thickness of the heaters, the temperature distribution on the mounting surface can be reduced, thereby improving the thermal uniformity of the mounting surface.

[0009] (2) In the holding device of the above embodiment, the heater section may have a fourth region located inside a ring-shaped area formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-shaped section, and the fourth heater arranged in the fourth region may include a heating wire and a pair of pads connected to both ends of the heating wire. According to this configuration, in the heater section, the fourth region located inside the ring-shaped area formed by the first region, the second region, and the third region includes a fourth heater arranged therein, the fourth heater including a heating wire and a pair of pads connected to both ends of the heating wire. In this configuration, even if the heater thickness has a directional characteristic due to, for example, a manufacturing method of the holding device, the first heater, the second heater, and the third heater arranged to surround the fourth region are connected in parallel to each other, thereby minimizing the temperature distribution on the mounting surface. This improves the thermal uniformity of the mounting surface.

[0010] (3) In the holding device of the above embodiment, the heater unit may have a fourth region having a ring shape and located inside a ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-shaped portion, and a fifth region located inside the fourth region in a plan view of the mounting surface of the plate-shaped portion, and the fourth heater arranged in the fourth region and the fifth heater arranged in the fifth region may be connected in parallel to each other. According to this configuration, the heater unit has the fourth region having a ring shape in which the fourth heater is arranged located inside the ring shape formed by the first region, the second region, and the third region, and the fifth region in which the fifth heater is arranged located inside the fourth region. Since the fourth heater and the fifth heater are connected in parallel to each other, the same voltage is applied. As a result, the relationship between the heat generation amounts of the heaters is inversely proportional to the magnitude of the electrical resistance of each heater, thereby further improving the temperature uniformity of the mounting surface.

[0011] (4) In the holding device of the above embodiment, the heater unit may include a sixth region having a ring shape and located outside the ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-shaped portion, and a seventh region having a ring shape and located outside the sixth region in a plan view of the mounting surface of the plate-shaped portion, and the sixth heater and the seventh heater may be connected in parallel to each other. According to this configuration, the sixth region having a ring shape in which the sixth heater is located is located outside the ring shape formed by the first region, the second region, and the third region, and the seventh region in which the seventh heater is located is located outside the sixth region. Since the sixth heater and the seventh heater are connected in parallel to each other, the same voltage is applied. As a result, the relationship between the heat generation amounts of the heaters is inversely proportional to the magnitude of the electrical resistance of each heater, thereby improving thermal uniformity even when the mounting surface is large.

[0012] The present invention can be realized in various forms, such as a method for manufacturing a holding device, a system including a holding device, a control method for these devices and systems, a computer program for causing these devices and systems to hold objects, a server device for distributing the computer program, and a non-transitory storage medium on which the computer program is stored. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a perspective view of the holding device of the first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the holding device of the first embodiment. [Figure 3] 3A and 3B are diagrams illustrating a heater portion provided in the holding device of the first embodiment. [Figure 4] 3A and 3B are diagrams illustrating the connection relationship of heaters included in the heater section of the first embodiment. [Figure 5] 5A to 5C are diagrams illustrating a manufacturing method of the holding device of the first embodiment. [Figure 6]10A and 10B are diagrams illustrating the amount of heat generated in a heater portion of a holding device of a comparative example. [Figure 7] 5A and 5B are diagrams illustrating the amount of heat generated in a heater portion of the holding device of the first embodiment. [Figure 8] 10A and 10B are diagrams illustrating the configuration of a heater unit included in a holding device according to a second embodiment. [Figure 9] 10A and 10B are diagrams illustrating the connection relationship of heaters included in a heater section according to a second embodiment. [Figure 10] 10A and 10B are diagrams illustrating a heater portion provided in a holding device according to a third embodiment. [Figure 11] 10A and 10B are diagrams illustrating the connection relationship of heaters included in a heater section according to a third embodiment. [Figure 12] 10A and 10B are diagrams illustrating a heater portion provided in a holding device according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] First Embodiment FIG. 1 is a perspective view of a holding device 1 of this embodiment. FIG. 2 is a cross-sectional view of the holding device 1 of this embodiment. The holding device 1 of this embodiment is an electrostatic chuck that attracts and holds an object such as a wafer W by electrostatic attraction. The electrostatic chuck is used, for example, as a table on which the wafer W (object) is placed in a chamber. The holding device 1 includes a ceramic part 10, a base part 20, and a bonding part 30. In the holding device 1 of this embodiment, as shown in FIG. 1, the ceramic part 10, the bonding part 30, and the base part 20 are stacked in this order. For convenience, in FIGS. 1 and 2, the stacking direction of the ceramic part 10, the bonding part 30, and the base part 20 is shown as the z-axis direction, the x-axis perpendicular to the z-axis is shown as the x-axis, and the y-axis perpendicular to the z-axis and x-axis is shown as the y-axis.

[0015] The ceramic portion 10 is a generally disk-shaped component whose main component is ceramic. Here, "main component" refers to the component with the highest content. The ceramic portion 10 of this embodiment is mainly composed of alumina (Al2O3). The ceramic portion 10 includes a plate-shaped portion 11, a heater portion 12, and a chuck electrode 13.

[0016] The plate-shaped portion 11 is a component made of ceramic and has a substantially circular disk shape. The plate-shaped portion 11 of this embodiment is made of alumina and has substantially the same shape as the ceramic portion 10. The material forming the plate-shaped portion 11 may be other ceramic materials such as aluminum nitride (AlN) or silicon carbide (SiC). The plate-shaped portion 11 has a mounting surface 11a on which the wafer W is mounted.

[0017] The heater section 12 is disposed inside the plate-shaped section 11 so as to face the mounting surface 11a. The heater section 12 of this embodiment has a plurality of heaters H12. The plurality of heaters H12 are connected to an external power supply via power supply terminals 12a for the heaters H12. When power is supplied from the external power supply, the heater section 12 generates heat capable of heating the wafer W mounted on the mounting surface 11a. Details of the heater section 12 will be described later.

[0018] The chuck electrode 13 is disposed inside the plate-shaped portion 11. The chuck electrode 13 is formed of a conductive material such as tungsten (W), molybdenum (Mo), or platinum (Pt). The chuck electrode 13 is connected to an external power supply via a chuck electrode terminal 13a. When power is supplied from the external power supply, the chuck electrode 13 generates an electrostatic attraction force capable of attracting and holding the wafer W on the mounting surface 11a of the plate-shaped portion 11. In this embodiment, the chuck electrode 13 is disposed farther from the mounting surface 11a than the heater portion 12, as shown in FIG. 2 . However, the positional relationship between the heater portion 12 and the chuck electrode 13 inside the plate-shaped portion 11 is not limited thereto. The chuck electrode 13 may be closer to the mounting surface 11a than the heater portion 12. In addition to the heater portion 12 and the chuck electrode 13, a high-frequency electrode or the like may be disposed inside the ceramic portion 10.

[0019] The base portion 20 is a generally disk-shaped component whose main component is, for example, a metal such as aluminum or an aluminum alloy, a metal-based composite such as an Al-SiC composite, or a ceramic such as silicon carbide (SiC). In this embodiment, the base portion 20 is made of aluminum. In this embodiment, the base portion 20 is larger than the ceramic portion 10. For example, if the diameter of the ceramic portion 10 is 300 mm, the diameter of the base portion 20 is 340 mm. Note that the size relationship between the ceramic portion 10 and the base portion 20 is not limited to this. They may be the same size.

[0020] A plurality of coolant flow paths 21 are formed inside the base portion 20. A coolant such as a fluorine-based inert liquid or water flows through the coolant flow paths 21. This cools the base portion 20, and therefore the ceramic portion 10 is cooled via the bonding portion 30.

[0021] The bonding portion 30 bonds the ceramic portion 10 and the base portion 20. The bonding portion 30 is, for example, a bonding sheet containing a silicone-based organic bonding agent, an inorganic bonding agent, or an Al-based metal adhesive. It is desirable for the bonding portion 30 to have high adhesive strength to both the ceramic portion 10 and the base portion 20, as well as high pressure resistance and high thermal conductivity.

[0022] Next, the features of the holding device 1 of this embodiment will be described. The heater section 12 included in the holding device 1 has a circular shape in a plan view of the mounting surface 11a of the plate-shaped section 11. The heater section 12 has a first region, a second region, and a third region that are arranged so as to form at least a part of a ring shape in a plan view of the mounting surface 11a of the plate-shaped section 11.

[0023] FIG. 3 is a diagram illustrating the configuration of the heater section 12 included in the holding device 1 of this embodiment. FIG. 3 shows a plan view of the mounting surface 11a of the plate-shaped portion 11 of the ceramic portion 10, i.e., a view from the positive side in the z-axis direction. The heater section 12 of this embodiment has a first region R1, a second region R2, and a third region R3. In FIG. 3, the first region R1, the second region R2, and the third region R3 are each illustrated as regions surrounded by two-dot chain lines. The first region R1, the second region R2, and the third region R3 are arranged to form the outer periphery of the heater section 12, which has a circular shape. The first region R1, the second region R2, and the third region R3 form a first annular region Rc1 in the heater section 12, which has a ring shape centered on the central axis C1 of the holding device 1.

[0024] The heater portion 12 of the ceramic portion 10 included in the holding device 1 of this embodiment has a central region Rc0 located inside the annular shape formed by the first region R1, the second region R2, and the third region R3 in a plan view of the mounting surface 11a of the plate-shaped portion 11. The central region Rc0 has a circular shape centered on the central axis C1 of the holding device 1, and is located inside the first annular region Rc1.

[0025] The holding device 1 of this embodiment has a plurality of heaters H12, including a first heater H1, a second heater H2, a third heater H3, and a central heater H0. In the holding device 1 of this embodiment, one heater is arranged in each region. Specifically, the first heater H1 is arranged in the first region R1, the second heater H2 is arranged in the second region R2, the third heater H3 is arranged in the third region R3, and the central heater H0 is arranged in the central region Rc0.

[0026] In the holding device 1 of this embodiment, each heater comprises a heating wire and a pair of pads connected to both ends of the heating wire. Specifically, the first heater H1 comprises a heating wire E1 and a pair of pads P1a, P1b connected to both ends of the heating wire E1. The second heater H2 comprises a heating wire E2 and a pair of pads P2a, P2b connected to both ends of the heating wire E2. The third heater H3 comprises a heating wire E3 and a pair of pads P3a, P3b connected to both ends of the heating wire E3. The central heater H0 comprises a heating wire E0 and a pair of pads P0a, P0b connected to both ends of the heating wire E0.

[0027] 4 is a diagram illustrating the connection relationship of the heaters in the heater section of the first embodiment. Next, the connection relationship between the heaters H1, H2, H3, and H0 in the heater section 12 and the power supplies that supply power thereto will be described. In order to make the connection relationship of the multiple heaters H1, H2, H3, and H0 easier to understand, FIG. 4 shows two power supplies PSc and PS1 that supply power to the heaters in the central region Rc0 and the first annular region Rc1, respectively. However, one power supply may be used to supply power to one holding device.

[0028] The first heater H1, second heater H2, and third heater H3 arranged in the first region R1, second region R2, and third region R3, respectively, that form the first annular region Rc1, are connected in parallel to a power supply PS1, as shown in Fig. 4. Specifically, the pad portions P1a and P1b of the first heater H1 are directly connected to the power supply PS1, the pad portions P2a and P2b of the second heater H2 are directly connected to the power supply PS1, and the pad portions P3a and P3b of the third heater H3 are directly connected to the power supply PS1. The central heater H0 arranged in the central region Rc0 is connected one-to-one to a power supply PSc.

[0029] Next, a description will be given of a method for manufacturing the retaining device 1. In the method for manufacturing the retaining device 1, the ceramic part 10 and the base part 20 are manufactured separately, and the separately manufactured ceramic part 10 and base part 20 are joined by a joining part 30.

[0030] The method for manufacturing the ceramic portion 10 begins with preparing a slurry for the green sheet and a metallization paste. The slurry for the green sheet is prepared by, for example, adding an organic solvent to a mixture containing alumina powder, an acrylic binder, a dispersant, a plasticizer, etc., and mixing the mixture using a ball mill. The metallization paste is prepared by, for example, adding a conductive powder such as tungsten or molybdenum to a mixture of alumina powder, an acrylic binder, and an organic solvent, and kneading the mixture.

[0031] The prepared green sheet slurry is formed into a sheet using a casting device, and the formed product is dried. This produces a green sheet. On a specific one of the green sheets, portions that will become heaters H1, H2, H3, and H0 of the heater section 12 are printed using a metallization paste, for example, using a screen printing device. A stack of green sheets is then produced by stacking multiple green sheets, including the specific green sheet on which the metallization paste has been printed. The green sheet stack is fired in an electric furnace to produce the ceramic section 10. In a method for manufacturing the base section 20, multiple metal plates, each having a processed portion that will become the refrigerant flow path 21, are stacked. Note that the methods for manufacturing the ceramic section 10 and the base section 20 are not limited to these.

[0032] In the manufacturing method of the holding device 1, a joining sheet that becomes the joining portion 30 is placed on the surface of either the ceramic portion 10 or the base portion 20, which are manufactured separately. For example, the joining sheet is placed on the surface of the base portion 20, and the joining sheet is sandwiched between the ceramic portion 10 and the base portion 20, and the whole is heated, thereby joining the ceramic portion 10 and the base portion 20 by the joining portion 30. In this manner, the holding device 1 is manufactured. However, the manufacturing method of the holding device 1 is not limited to this.

[0033] In the manufacturing method of the holding device 1 described above, the heaters H1, H2, H3, and H0 are formed on the green sheet by printing metallization paste with a screen printing device. When forming the heater portions using a screen printing device, the thickness of the heater portions may have a certain directionality due to the printing direction.

[0034] FIG. 5 is a diagram illustrating a manufacturing method of the holding device 1 of this embodiment. FIG. 5 shows a schematic diagram e10 illustrating a plan view of a ceramic part, and a graph g5 illustrating an example of the change in thickness of a heater formed by a screen printing device. The schematic diagram e10 shows the x-axis, y-axis, and z-axis representing the directions of the ceramic part. The ceramic part shown in the schematic diagram e10 has a circular region Re0 in which the heater is disposed.

[0035] In graph g5 shown in Figure 5, the vertical axis p1 represents the position on the ceramic component shown in schematic diagram e10, and the horizontal axis t1 represents the thickness of the heater portion formed on the green sheet by a screen printing device using metallization paste. In screen printing using metallization paste, for example, as shown in Figure 5, the metallization paste is printed on the ceramic component along the direction of the white arrow F1 from the most positive point Pa in the y-axis direction to the most negative point Pb in the y-axis direction. When the metallization paste is printed in this manner, due to the characteristics of screen printing, the thickness of the heater portion gradually decreases from the point Pa where the screen printing begins to the point Pb, as shown in graph g5 in Figure 5. This directional thickness of the heater portion also leads to a directional distribution of the electrical resistance of the heater. Specifically, as shown in Figure 5, if virtual heaters Ha, Hb, Hc, and Hd are formed in this order from point Pa to point Pb, and the thickness of the parts that will become the heaters has a directionality as shown in graph g5 in Figure 5, the thickness of the metallization paste that will become the heaters will become thinner in the order of heater Ha, heater Hb, heater Hc, and heater Hd, and therefore the electrical resistance will become greater in the order of heater Ha, heater Hb, heater Hc, and heater Hd.

[0036] FIG. 6 is a diagram illustrating the amount of heat generated by a heater included in a holding device of a comparative example. The holding device 1s of the comparative example shown in FIG. 6 includes a ceramic portion 90, a base portion 20, and a joint portion (not shown). The ceramic portion 90 includes a plate-shaped portion 91 formed of ceramic and having a substantially circular plate shape, a heater portion 92, and a chuck electrode (not shown). The heater portion 92 includes multiple heaters H91, H92, and H93. The heater portion 92 includes a circular central region R91 encompassed by a central axis C1s of the holding device 1s, an annular region R92 disposed outside the central region R91, and an annular region R93 disposed outside the annular region R92. The annular regions R92 and R93 of the heater portion 92 of the holding device 1s of the comparative example correspond to the first annular region Rc1 of the heater portion 12 of the holding device 1 of this embodiment. A heater H91 is arranged in the central region R91, a heater H92 is arranged in the annular region R92, and a heater H93 is arranged in the annular region R93. In the holding device 1s of the comparative example, as shown in Fig. 6, the heater H92 in the annular region R92 and the heater H93 in the annular region R93 are connected in series to a power source PS1.

[0037] In FIG. 6, the ranges corresponding to the heaters Ha, Hb, Hc, and Hd shown in FIG. 5 are shown overlapping the heater portion 92 of the holding device 1s of the comparative example. In FIG. 6, the amount of heat generated in each of the ranges corresponding to the heaters Ha, Hb, Hc, and Hd is indicated by the density of hatched dots, with higher density indicating a higher heat generation amount. In the configuration of the holding device 1s of the comparative example shown in FIG. 6, if there is a directionality in the thickness of the heater portion as described in FIG. 5, the ranges corresponding to the heaters Ha and Hd overlap in the heaters H92 and H93, resulting in significantly different electrical resistances within the heaters. Because the heaters H92 and H93 are connected in series, the same current flows through the heaters H92 and H93. Therefore, the heat generation amount calculated by multiplying the electrical resistance and the square of the current between heaters H92 and H93 differs significantly between the heater Ha and the heater Hd. Specifically, the heat generation amount in the heater Hd is greater than that in the heater Ha. Similarly, for heater H91, the heat generation amount in the heater Hc is greater than that in the heater Hb. As a result, in the holding device 1s of the comparative example, the negative side of the y-axis is likely to be hotter and the positive side of the y-axis is likely to be colder. Furthermore, on the negative side of the y-axis, where the heater is likely to be hotter, the electrical resistance of the heater increases due to the influence of temperature, further increasing the temperature difference between the negative side of the y-axis and the positive side of the y-axis. Thus, in the holding device 1 of the comparative example, if the heater portion is formed by screen printing using a metallization paste, the temperature distribution on the support surface is likely to be large. In other words, the holding device 1s of the comparative example is likely to have poor thermal uniformity on the support surface.

[0038] 7 is a diagram illustrating the amount of heat generated in the heater section of the holding device of this embodiment. In the holding device 1 of this embodiment, the first annular region Rc1 of the heater section 12 has a first region R1 where the first heater H1 is disposed, a second region R2 where the second heater H2 is disposed, and a third region R3 where the third heater H3 is disposed. The first heater H1, the second heater H2, and the third heater H3 are each connected in parallel to a power source PS1 as shown in FIG. 7. As a result, the relationship between the amount of heat generated by each of the first heater H1, the second heater H2, and the third heater H3 is calculated by dividing the square of the voltage by the electrical resistance, and is therefore inversely proportional to the magnitude of the electrical resistance. Therefore, in the holding device 1 of this embodiment, even if the heat generation amount of the central heater H0 in the central region Rc0 has the same directionality as the heater H91 in the central region R91 in the holding device 1s of the comparative example, in the first annular region Rc1, a relatively high-temperature portion of the central heater H0 (the range corresponding to heater Hc) is adjacent to a relatively low-temperature portion (the range corresponding to heater Hd), and a relatively low-temperature portion of the central heater H0 (the range corresponding to heater Hb) is adjacent to a relatively high-temperature portion (the range corresponding to heater Ha) This improves the thermal uniformity on the mounting surface 10a.

[0039] In the holding device 1 of this embodiment, the area of ​​the first annular region Rc1 corresponding to the heater Ha becomes relatively high temperature, and therefore the portion of the second heater H2 corresponding to the heater Ha has a relatively high electrical resistance. However, because the first heater H1, the second heater H2, and the third heater H3 arranged in the first annular region Rc1 are connected in parallel to the power supply PS1, the amount of heat generated in the portion of the second heater H2 corresponding to the heater Ha is prevented from becoming excessively large. This further improves the thermal uniformity on the mounting surface 10a.

[0040] According to the holding device 1 of the present embodiment described above, the plate-shaped portion 11, which has a mounting surface 11a on which a wafer W is mounted, includes a heater unit 12 disposed opposite the mounting surface 11a. The heater unit 12 has a first region R1, a second region R2, and a third region R3 that are arranged to form at least a part of a ring shape in a plan view of the mounting surface 11a of the plate-shaped portion 11. A first heater H1, a second heater H2, and a third heater H3 that are connected in parallel to each other are disposed in the first region R1, the second region R2, and the third region R3, respectively. As a result, the same voltage is applied to the first heater H1, the second heater H2, and the third heater H3, and the relationship between the heat generation amounts of the heaters is inversely proportional to the magnitude of the electrical resistance of each heater. Therefore, even if there is variation in the thickness of the heater, the temperature distribution on the mounting surface 11a can be reduced, and the temperature uniformity on the mounting surface 11a can be improved.

[0041] Furthermore, according to the holding device 1 of this embodiment, the heater section 12 includes a central region Rc0 located inside the ring-shaped region formed by the first region R1, the second region R2, and the third region R3. The central region Rc0 includes a central heater H0, which is composed of a heating wire E0 and a pair of pads P0a and P0b connected to both ends of the heating wire E0. Even if the manufacturing method of the holding device 1 results in a directionality in the heater thickness, the first heater H1, the second heater H2, and the third heater H3, which are located in the first region R1, the second region R2, and the third region R3 surrounding the central region Rc0, are connected in parallel to each other, thereby minimizing the temperature distribution on the mounting surface 11a. This improves the thermal uniformity of the mounting surface 11a.

[0042] Second Embodiment 8 is a diagram illustrating the configuration of a heater unit included in the holding device 2 of the second embodiment. Compared to the holding device 1 of the first embodiment (FIG. 3), the holding device 2 of the second embodiment differs in the shape of the area located inside the first annular area Rc1 and in the way the heater located in the area inside the first annular area Rc1 is connected to the power source.

[0043] The holding device 2 of the second embodiment includes a ceramic part 40, a base part 20, and a bonding part 30. The holding device 2 of the present embodiment is, for example, an electrostatic chuck that attracts and holds an object such as a wafer W by electrostatic attraction.

[0044] The ceramic portion 40 is a generally disk-shaped component made primarily of alumina. The ceramic portion 40 includes a plate-shaped portion 11, a heater portion 42, and a chuck electrode 13. The heater portion 42 is disposed inside the plate-shaped portion 11 so as to face the mounting surface 11a. In this embodiment, the heater portion 42 includes a plurality of heaters H42. The heaters H42 are connected to an external power supply via power supply terminals 12a for the heaters H42. When power is supplied from the external power supply, the heater portion 42 generates heat capable of heating the wafer W mounted on the mounting surface 11a.

[0045] The heater section 42 has a circular shape in a plan view of the mounting surface 11a of the plate-shaped section 11. The heater section 42 has a fourth region R4 that is located inside the ring shape formed by the first region R1, the second region R2, and the third region R3 that form the first annular region Rc1, and has a fifth region R5 that is located inside the fourth region R4. The fifth region R5 has a circular shape centered on the central axis C2 of the holding device 2.

[0046] The holding device 2 of this embodiment has a plurality of heaters H42, including a first heater H1, a second heater H2, a third heater H3, a fourth heater H4, and a fifth heater H5. In the holding device 2 of this embodiment, one heater is arranged in each region. Specifically, the first heater H1 is arranged in the first region R1, the second heater H2 is arranged in the second region R2, and the third heater H3 is arranged in the third region R3. The fourth heater H4 is arranged in the fourth region R4, and the fifth heater H5 is arranged in the fifth region R5.

[0047] In the holding device 2 of this embodiment, each heater comprises a heating wire and a pair of pads connected to both ends of the heating wire. The first heater H1, second heater H2, and third heater H3 are the same as those in the first embodiment. The fourth heater H4 comprises a heating wire E4 and a pair of pads P4a and P4b connected to both ends of the heating wire E4. The fifth heater H5 comprises a heating wire E5 and a pair of pads P5a and P5b connected to both ends of the heating wire E5.

[0048] 9 is a diagram illustrating the connection relationship of the heaters in the heater section 42 of this embodiment. The first heater H1, second heater H2, and third heater H3, which are arranged in the first region R1, second region R2, and third region R3 that form the first annular region Rc1, respectively, are connected in parallel to a power supply PS1. The fourth heater H4 arranged in the fourth region R4 and the fifth heater H5 arranged in the fifth region R5 are connected in parallel to a power supply PSc. Specifically, the pads P4a and P4b of the fourth heater H4 are directly connected to the power supply PSc, and the pads P5a and P5b of the fifth heater H5 are directly connected to the power supply PSc.

[0049] According to the holding device 2 of the present embodiment described above, the first region R1, the second region R2, and the third region R3 of the heater section 42 are respectively provided with the first heater H1, the second heater H2, and the third heater H3, which are connected in parallel to one another. As a result, the same voltage is applied to the first heater H1, the second heater H2, and the third heater H3, respectively, and therefore, even if the heaters vary in thickness, the temperature distribution on the mounting surface 11a can be reduced. This improves the thermal uniformity of the mounting surface 11a.

[0050] Furthermore, in the heater section 42 of the holding device 2 of this embodiment, the fourth region R4, which has an annular shape and in which the fourth heater H4 is disposed, is located inside the annular shape formed by the first region R1, the second region R2, and the third region R3, and the fifth region R5, in which the fifth heater H5 is disposed, is located inside the fourth region R4. The fourth heater H4 and the fifth heater H5 are connected in parallel to each other, and therefore the same voltage is applied to them. As a result, the relationship between the heat generation amounts of the fourth heater H4 and the fifth heater H5 is inversely proportional to the magnitude of the electrical resistance of the fourth heater H4 and the fifth heater H5, thereby further improving the thermal uniformity of the mounting surface 11a.

[0051] Third Embodiment 10 is a diagram illustrating a heater unit provided in the holding device 3 of the third embodiment. The holding device 3 of the third embodiment differs from the holding device 2 of the second embodiment (FIG. 8) in that the heater unit has an area where the heater is arranged outside the first annular area Rc1.

[0052] The holding device 3 of the third embodiment includes a ceramic part 50, a base part 20, and a bonding part 30. The holding device 3 of the present embodiment is, for example, an electrostatic chuck that attracts and holds an object such as a wafer W by electrostatic attraction.

[0053] The ceramic portion 50 is a generally circular plate-shaped component primarily composed of alumina. The ceramic portion 50 includes a plate-shaped portion 11, a heater portion 52, and a chuck electrode 13. The heater portion 52 is disposed inside the plate-shaped portion 11 so as to face the mounting surface 11a. In this embodiment, the heater portion 52 includes a plurality of heaters H52. The heaters H52 are connected to an external power supply via power supply terminals 12a for the heaters H52. When power is supplied from the external power supply, the heater portion 52 generates heat sufficient to heat the wafer W mounted on the mounting surface 11a. Note that the base portion 20 is omitted from FIG. 10, which shows a schematic plan view of the mounting surface 11a of the plate-shaped portion 11, to avoid cluttering the drawing.

[0054] The heater section 52 has a circular shape in a plan view of the mounting surface 11a of the plate-shaped portion 11. The heater section 52 has a sixth region R6 having a ring shape located outside the ring shape formed by the first region R1, the second region R2, and the third region R3 in a plan view of the mounting surface 11a of the plate-shaped portion 11, and a seventh region R7 having a ring shape located outside the sixth region R6. In the heater section 52, the sixth region R6 and the seventh region R7 form a second annular region Rc2 having a ring shape centered on the central axis C3 of the holding device 3. The heater section 52 of this embodiment has a fourth region R4 having a ring shape located inside the ring shape formed by the first region R1, the second region R2, and the third region R3, and a fifth region R5 located inside the fourth region R4.

[0055] The holding device 3 of this embodiment has multiple heaters H52, including a first heater H1, a second heater H2, a third heater H3, a fourth heater H4, a fifth heater H5, a sixth heater H6, and a seventh heater H7. In the holding device 3 of this embodiment, one heater is arranged in each region. Specifically, the first heater H1 is arranged in the first region R1, the second heater H2 is arranged in the second region R2, and the third heater H3 is arranged in the third region R3. The fourth heater H4 is arranged in the fourth region R4, and the fifth heater H5 is arranged in the fifth region R5. The sixth heater H6 is arranged in the sixth region R6, and the seventh heater H7 is arranged in the seventh region R7.

[0056] In the holding device 3 of this embodiment, each heater comprises a heating wire and a pair of pads connected to both ends of the heating wire. The first heater H1, second heater H2, and third heater H3 are the same as those in the first embodiment. The fourth heater H4 and fifth heater H5 are the same as those in the second embodiment. The sixth heater H6 comprises a heating wire E6 and a pair of pads P6a and P6b connected to both ends of the heating wire E6. The seventh heater H7 comprises a heating wire E7 and a pair of pads P7a and P7b connected to both ends of the heating wire E7.

[0057] FIG. 11 is a diagram illustrating the connections of the heaters in the heater unit 52 of this embodiment. In the heater unit 52, the first heater H1, the second heater H2, and the third heater H3, which are arranged in the first region R1, the second region R2, and the third region R3 that form the first annular region Rc1, respectively, are connected in parallel to a power supply PS1. The fourth heater H4 and the fifth heater H5, which are arranged in the fourth region R4 and the fifth region R5, respectively, which are located inside the first annular region Rc1, are connected in parallel to a power supply PSc. The sixth heater H6 and the seventh heater H7, which are arranged in the sixth region R6 and the seventh region R7, are connected in parallel to a power supply PS2. Specifically, the pads P6a and P6b of the sixth heater H6 are directly connected to the power supply PS2, and the pads P7a and P7b of the seventh heater H7 are directly connected to the power supply PS2. In Figure 11, in order to make the connection relationship of multiple heaters H52 easier to understand, three power sources PSc, PS1, and PS2 are shown supplying power to the heaters in the central region Rc0, the first annular region Rc1, and the second annular region Rc2, respectively, but one power source may be used to supply power to one holding device.

[0058] According to the holding device 3 of this embodiment described above, the first region R1, the second region R2, and the third region R3 of the heater section 52 are respectively provided with the first heater H1, the second heater H2, and the third heater H3, which are connected in parallel to one another. As a result, the same voltage is applied to the first heater H1, the second heater H2, and the third heater H3, respectively, and therefore, even if the heaters vary in thickness, the temperature distribution on the mounting surface 11a can be reduced. This improves the thermal uniformity of the mounting surface 11a.

[0059] Furthermore, according to the holding device 3 of this embodiment, the heater section 52 has a sixth region R6 having an annular shape in which the sixth heater H6 is disposed located outside the annular shape formed by the first region R1, the second region R2, and the third region R3, and a seventh region R7 in which the seventh heater H7 is disposed located outside the sixth region R6. The sixth heater H6 and the seventh heater H7 are connected in parallel with each other, and therefore the same voltage is applied to them. As a result, the relationship between the heat generation amounts of the sixth heater H6 and the seventh heater H7 is inversely proportional to the magnitude of the electrical resistance of each of the sixth heater H6 and the seventh heater H7. Therefore, even if the mounting surface 11a is large, the temperature uniformity can be improved.

[0060] <Fourth embodiment> 12 is a diagram illustrating a heater unit provided in the holding device 4 of the fourth embodiment. The holding device 4 of the fourth embodiment differs from the holding device 3 of the third embodiment (FIG. 10) in that the heater unit has a region where the heater is arranged outside the second annular region Rc2 having a ring shape.

[0061] The holding device 4 of the fourth embodiment includes a ceramic part 60, a base part 20, and a bonding part 30. The holding device 3 of the present embodiment is, for example, an electrostatic chuck that attracts and holds an object such as a wafer W by electrostatic attraction.

[0062] The ceramic portion 60 is a generally disk-shaped component primarily composed of alumina. The ceramic portion 60 includes a plate-shaped portion 11, a heater portion 62, and a chuck electrode 13. The heater portion 62 is disposed inside the plate-shaped portion 11 so as to face the mounting surface 11a. In this embodiment, the heater portion 62 includes multiple heaters. The multiple heaters are connected to an external power supply via a power supply terminal 12a. When power is supplied from the external power supply, the heater portion 62 generates heat sufficient to heat the wafer W mounted on the mounting surface 11a. Note that in FIG. 12, which shows a schematic plan view of the mounting surface 11a of the plate-shaped portion 11, the shapes of the base portion 20 and the multiple heaters of the heater portion 62 are omitted to avoid cluttering the drawing.

[0063] The heater section 62 has a circular shape in a plan view of the mounting surface 11a of the plate-shaped portion 11. The heater section 62 has an eighth region R8, a ninth region R9, a tenth region R10, and an eleventh region R11 arranged to form a ring shape in a plan view of the mounting surface 11a of the plate-shaped portion 11. The eighth region R8, the ninth region R9, the tenth region R10, and the eleventh region R11 form a third annular region Rc3 located outside the seventh region R7. A sixth region R6 having a ring shape is located inside the seventh region R7, and a first annular region Rc1 formed by the first region R1, the second region R2, and the third region R3 is located inside the sixth region R6. A fourth region R4 having a ring shape and a fifth region R5 located inside the fourth region R4 are located inside the first annular region Rc1.

[0064] In the holding device 4 of this embodiment, one heater is arranged in one region. The heaters arranged in the eighth region R8, the ninth region R9, the tenth region R10, and the eleventh region R11 are connected in parallel to each other to an external power supply (not shown).

[0065] According to the holding device 4 of this embodiment described above, the heaters arranged in the eighth region R8, the ninth region R9, the tenth region R10, and the eleventh region R11 of the heater section 62 are connected in parallel to each other. As a result, the same voltage is applied to the heaters arranged in the eighth region R8, the ninth region R9, the tenth region R10, and the eleventh region R11. Therefore, even if the heaters vary in thickness, the temperature distribution on the mounting surface 11a can be reduced. This improves the thermal uniformity of the mounting surface 11a.

[0066] <Modification of this embodiment> The present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit of the invention. For example, the following modifications are also possible.

[0067] [Variation 1] In the above-described embodiment, the first region, second region, and third region of the heater portion are arranged to form a ring shape in a plan view of the mounting surface 11a of the plate-shaped portion 11. However, the first region may be arranged so that three regions form at least a part of the ring shape. For example, the first annular region Rc1 may be formed by four or more regions including the first region, the second region, and the third region.

[0068] [Variation 2] In the above-described embodiment, one heater disposed in each of the multiple regions includes a heating wire and a pair of pads connected to both ends of the heating wire. However, the heater configuration is not limited to this. For example, the first heater disposed in the first region R1 may include multiple heating wires and multiple pairs of pads connected to both ends of the multiple heating wires, as long as the multiple heating wires are connected in parallel to the power supply.

[0069] [Variation 3] In the third embodiment, the heater section 52 has a fourth region R4 having an annular shape, a fifth region R5 located inside the fourth region R4, a first annular region Rc1 located outside the fourth region R4, and a second annular region Rc2 located outside the first annular region Rc1. The fourth region R4 and the fifth region R5 do not necessarily have to be located inside the first annular region Rc1, and a circular central region Rc0 may be located therein as in the first embodiment.

[0070] [Variation 4] In the above-described embodiment, the holding device includes a ceramic portion mainly composed of ceramic, a base portion made of metal, and a joining portion joining the ceramic portion and the base portion. The configuration of the holding device is not limited to this. The entire holding device may be made of ceramic, or may be made of a composite material of ceramic and metal.

[0071] This aspect has been described above based on embodiments and modifications. However, the above-described embodiments are intended to facilitate understanding of this aspect and are not intended to limit this aspect. This aspect may be modified or improved without departing from the spirit and scope of the claims, and equivalents thereof are included in this aspect. Furthermore, if a technical feature is not described as essential in this specification, it may be deleted as appropriate.

[0072] <Application example 1> A holding device, a plate-like portion having a placement surface on which an object is placed; a heater portion disposed inside the plate-shaped portion so as to face the placement surface, The heater unit includes: The plate-shaped portion has a first region, a second region, and a third region that are arranged to form at least a part of a ring shape in a plan view of the mounting surface, a first heater disposed in the first region, a second heater disposed in the second region, and a third heater disposed in the third region, each being connected in parallel with one another; holding device. <Application example 2> The holding device according to Application Example 1, the heater portion has a fourth region located inside a ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-like portion, The fourth heater disposed in the fourth region includes: A heating wire and a pair of pad portions connected to both ends of the heating wire, holding device. <Application example 3> The holding device according to Application Example 1 or Application Example 2, The heater unit includes: a fourth region having a ring shape and located inside a ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-shaped portion; a fifth region located inside the fourth region in a plan view of the mounting surface of the plate-shaped portion, The fourth heater disposed in the fourth region and the fifth heater disposed in the fifth region are connected in parallel with each other. holding device. <Application Example 4> The holding device according to any one of Application Examples 1 to 3 may further include: The heater unit includes: a sixth region having a ring shape and located outside a ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-like portion; a seventh region having a ring shape and located outside the sixth region in a plan view of the mounting surface of the plate-shaped portion, The sixth heater arranged in the sixth region and the seventh heater arranged in the seventh region are connected in parallel with each other. holding device. [Explanation of symbols]

[0073] 1,2,3,4…holding device 11...Plate-shaped part 11a...Placement surface 12, 42, 52, 62...Heater section E0,E1,E2,E3,E4,E5,E6,E7…heating wire P0a, P0b, P1a, P1b, P2a, P2b, P3a, P3b, P4a, P4b, P5a, P5b, P6a, P6b, P7a, P7b...Pad section H0: Central heater H1: First heater H2: Second heater H3: Third heater H4: Fourth heater H5...5th heater H6...6th heater H7...7th heater R1…first area R2…Second area R3...Third area R4…4th area R5…The 5th Domain R6…The 6th Domain R7…7th Domain W…ウェハ

Claims

1. A holding device, a plate-like portion having a placement surface on which an object is placed; a heater section disposed inside the plate-shaped section so as to face the placement surface, The heater unit includes: the plate-shaped portion has a first region, a second region, and a third region that are arranged to form at least a part of a ring shape in a plan view of the mounting surface, a first heater disposed in the first region, a second heater disposed in the second region, and a third heater disposed in the third region, each being connected in parallel with one another; holding device.

2. 2. The holding device of claim 1, the heater portion has a fourth region located inside a ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-like portion, The fourth heater disposed in the fourth region includes: A heating wire and a pair of pad portions connected to both ends of the heating wire, holding device.

3. 2. The holding device of claim 1, The heater unit includes: a fourth region having a ring shape and located inside a ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-like portion; a fifth region located inside the fourth region in a plan view of the mounting surface of the plate-shaped portion, a fourth heater disposed in the fourth region and a fifth heater disposed in the fifth region are connected in parallel with each other; holding device.

4. The holding device according to claim 3 further comprises: The heater unit includes: a sixth region having a ring shape and located outside a ring shape formed by the first region, the second region, and the third region in a plan view of the mounting surface of the plate-like portion; a seventh region having an annular shape and located outside the sixth region in a plan view of the mounting surface of the plate-shaped portion, a sixth heater disposed in the sixth region and a seventh heater disposed in the seventh region are connected in parallel with each other; holding device.

Images